remove SRS pdf and fix spelling errors in Code

[Dimitris Kalamaras]

Caitlin Matos reports:

"As you may have noticed, the PDF manual has been removed from the Debian package. I have done this because PDF files without their source code violate the Debian Free Software Guidelines[1], namely:

    2. Source Code
    The program must include source code, and must allow distribution
    in source code as well as compiled form.

If you would like the PDF to be included, please include the source code so that the PDF can be rebuilt.

If you feel the PDF should be referred to in the manpage but don't mind the PDF itself not being installed in Debian, that can be done. Because the manpage is already gzipped, it is not straightforward to change the documentation for just the Debian package. Some ideas:
- provide the manpage in the tarball in an unzipped format
- add a link to the end of the manpage yourself
- let me know, and I'll do it the hack-y way for Debian :)

Also, lintian (Debian's linter) has caught some spelling mistakes in your source code that you may want to fix, and I've added some others:

   Numerous places: betweeness should be betweenness (double n)

   src/mainwindow.cpp
   - 1207: out-likned -> out-linked
   - 1378: numnber -> number
   - 1380: oftenly -> often (grammar error)
   - 1509: Num&bers -> Numbers
   - 2018: consequetively -> consecutively
   - 2164: reppeling -> repelling
   - 2165: attact -> attract
   - 3418: vertice -> vertex
   - lines 3447 and 3494: grabing -> grabbing
   - 7529: pallette -> palette (also in corresponding lines in translations files)

   src/webcrawler.cpp: line 289: usefull -> useful

   manual/intro.html: line 191: usefull -> useful
"