autogen.sh: remove aclocal calls, not needed anymore

Since we stop using autoconf macros (such as PKG_CHECK_MODULES;
see [1]) in [2], aclocal is not likely to be needed anymore.

[1] http://tirania.org/blog/archive/2012/Oct-20.html
[2] https://github.com/fsharp/fsharp/commit/cded42fb1929f9ca1edcb5ecc38c052287caba0e
Cherry pick 3a1f5187baaf422a98a92001008334311827feb9 to align with base for F# 3.1 code drop
Integrate changes from Microsoft Visual F# source code drop http://fsharppowerpack.codeplex.com up to change 71609, including changes for VS2012 Update 2 - Portable Async and Query fixes
Minor textual changes to align fsharp/fsharp with fsharppowerpack.codeplex.com
Integrate updates from Visual F# team for Visual Studio 2012 Update 2
change to align 3.1 base with base for 3.0 code drop
Fix docs for bitwise operators
Align message text with original F# 3.0 code drop
Clean commit of Microsoft code drop for F# Compiler 3.1 from http://fsharppowerpack.codeplex.com/SourceControl/list/changesets change 72229
Integrate fsharp/fsharp master into fsharp_31
Minor adjustments to align source code and compile portable profile libraries
Simply build to use xbuild. Install targets into correct place. Adjust policy DLLs for F# 3.1
undo unintentionial changes in code drop
adjust version numbers and installation
fix mistake in previous commit
Allow projects to load in VS2013
minor textual cleanup to project file
Fixed build.bat so it works correctly when the repository has been checked out into a folder whose name contains one or more spaces.
Updates for F# 3.1 build on Linux
Merge recent changes in build with F# 3.1