doc: Remove recommendation to add old repos for libd4.8*

It is unreasonable to ask to change the global package configuration
just to build a package. Not only that, this is potentially harmful to the system.

Also do a few punctuation fixes in REST-interface.md.

doc/REST-interface.md

@@ -9,8 +9,7 @@ Supported API
 ####Transactions
 `GET /rest/tx/<TX-HASH>.<bin|hex|json>`
 
-Given a transaction hash,
+Given a transaction hash: returns a transaction in binary, hex-encoded binary, or JSON formats.
-Returns a transaction, in binary, hex-encoded binary or JSON formats.
 
 For full TX query capability, one must enable the transaction index via "txindex=1" command line / configuration option.
 
@@ -18,8 +17,7 @@ For full TX query capability, one must enable the transaction index via "txindex
 `GET /rest/block/<BLOCK-HASH>.<bin|hex|json>`
 `GET /rest/block/notxdetails/<BLOCK-HASH>.<bin|hex|json>`
 
-Given a block hash,
+Given a block hash: returns a block, in binary, hex-encoded binary or JSON formats.
-Returns a block, in binary, hex-encoded binary or JSON formats.
 
 The HTTP request and response are both handled entirely in-memory, thus making maximum memory usage at least 2.66MB (1 MB max block, plus hex encoding) per request.
 
@@ -28,8 +26,7 @@ With the /notxdetails/ option JSON response will only contain the transaction ha
 ####Blockheaders
 `GET /rest/headers/<COUNT>/<BLOCK-HASH>.<bin|hex|json>`
 
-Given a block hash,
+Given a block hash: returns <COUNT> amount of blockheaders in upward direction.
-Returns <COUNT> amount of blockheaders in upward direction.
 
 ####Chaininfos
 `GET /rest/chaininfo.json`

doc/build-unix.md

@@ -59,7 +59,7 @@ Build requirements:
 
 	sudo apt-get install build-essential libtool autotools-dev autoconf pkg-config libssl-dev
 	
-for Ubuntu 12.04 and later or Debian 7 and later libboost-all-dev has to be installed:
+For Ubuntu 12.04 and later or Debian 7 and later libboost-all-dev has to be installed:
 
 	sudo apt-get install libboost-all-dev
 
@@ -72,18 +72,7 @@ for Ubuntu 12.04 and later or Debian 7 and later libboost-all-dev has to be inst
  Ubuntu 12.04 and later have packages for libdb5.1-dev and libdb5.1++-dev,
  but using these will break binary wallet compatibility, and is not recommended.
 
-for Debian 7 (Wheezy) and later:
+For other Debian & Ubuntu (with ppa):
- The oldstable repository contains db4.8 packages.
- Add the following line to /etc/apt/sources.list,
- replacing [mirror] with any official debian mirror.
-
-	deb http://[mirror]/debian/ oldstable main
-
-To enable the change run
-
-	sudo apt-get update
-
-for other Debian & Ubuntu (with ppa):
 
 	sudo apt-get install libdb4.8-dev libdb4.8++-dev