Fixed Wolfram|Alpha bugs.

Did this by giving all operators an appropiate toString method with good
parenthesing. Strings returned by Symja were ambigious to Wolfram|Alpha
in some cases and by building our own query strings we lose this
ambuguity.
Add checks so that wolfram|alpha only queries when it can.
remove unneccecery toString method in MathObjectEmpty
Sinoids, by Ivor and Glenn.
You don't like it? deal with it
changing the way a Sinoid determines its boundingbox
added -1 to arcsin, arctan and arccos. 2 problems: 1) -1 is not seen as the operator, so on hover it does not turn blue ( combine 2 strings to make 1 operator?). 2) Operator bounding boxes are placed against the top of the complete boundingbox.
nothing done, just looking at what the problem could be
merge MathVariable and MathConstant to MathSymbol
sinoids bug fixes
Merge branch 'master' into work

Conflicts:
	src/org/teaminfty/math_dragon/view/fragments/FragmentMainScreen.java
Linear mathObject Bugfix. Double in Ivor's version :( this one's better
Code formatted and some javadoc updated
Code formatted and some javadoc updated
modified sinoids and made log and ln
Merge branch 'master' into work

Conflicts:
	src/org/teaminfty/math_dragon/view/fragments/FragmentMainScreen.java
Merge remote-tracking branch 'glenn/work' into pull
Fixed some issues that arised after the merge

Signed-off-by: Mark Kamsma <mark@markkamsma.nl>
Refactored MathSymbol. works a lot simpler now

Supports variables now as well.
Fixed comparison
fixen dat bij factor 1 de factor niet getekend wordt